Improvement in apparatus for metal-cqating metal plates



E. momwoon & J. H. ROGERS. APPARATUS FOR METAL-COATING METAL-PLATES.

"Patented J'an.11, 1876.

No.17Z,148.

H-FETERS, FHOTO'UTHOGRRPHER WASHINGTON, D. C.

the entrance to the deliy'ery rollers. .rangement lessens the amount offlux and UNI ED STATES PATENT QEEIGE.

EDMUND MoREwooD, 'oE LLANELLY, ANDfJoHN H. ROGERS, OF LLANGEN- N oHPARK, NEAR LLANELLY, GREAT BRITAIN.

IMPROVEMENT I N APPARATUS FOR METAL-CQATING METAL PLATES.

Specification forming part of LettersPatent No. 172,148, dated January11, 1876 ,application filed December 21, 1875.

To all whom it may concern:

Be it known that we, EDMUND MOREWOOD, of Llanelly, in the county ofCarmarthen, and JOHN HENRY ROGERS, of Llangennech Park,

' near Llanelly, in the county of Oarmarthen, Great Britain, tin-platemanufacturers, have invented certain improvements in applying tin orother coating metal to metal sheets and other surfaces of metal, ofwhich the following is a specification:

ln coating plates of iron with tin or other coatin g metal in a meltedstate, itis well known quantity of coating metal in a melted state,

we arrange machinery, vessels, and melted metal so as to make itunnecessary to sub merge the plates, either partially or wholly,

in the melted metal; and this we do by causing the molten coating metalto be supplied to the sheets or other surfaces while they are travelingthrough a bath of heated flux, which is efl'ected by rollers which arekept perpetually supplied with coating metal. The plates are thus, as itwere, coated by transfer and adhesion, while the ordinary method actsmore by soaking and combination, the coatingmetal channel or passagewaybetween said pot and:

cylinder for the plates to pass through from coating metal required inthe pot, and there i is but a small extent of surface of the flux in.

direct contact with the melted metal, and,

hence, prevents largely the deterioration of said flux.

- In applying coating metal according to our of coating-rollers,weproceed as follows: We

This arfirst clean or pickle the plates of metal with hot and strongacid, or, as it is usually termed, high, and after washing them Well inclean water, we use them fresh, say an hour or two after they have beencleaned, and without allowing them to stand long in water. We then placethem wet or damp, and, by preference, separately, in a grease pot orv'esset heated to about the melting-point of the metal with which theyare to be coated. The grease-pot is provided with an overflow gutter orpipe,

and an arrangement for the return in a more solid state of the greasewhich froths up and flows over when the wet iron plates are deposited inthe hot grease. Such an. arrange ment as that described in EdmundMorewoods British Patent of 22d June, 1870, No. 1,780, will answer, butis not claimed here. In

this grease-pot we usually have at one time, say, forty or fifty ironplates of the size technically described as 20x 14, 0 thickness, keepingthem as much apart as we conveniently. Y

can by means of pins or otherwise. The plates are deposited and removedas nearly as may be in rotation, and while in this grease-pot they areimmersed in hot and tolerably solid grease. From this grease-pot wewithdraw the hot plates, and treat them. by our improved process,according to which we pass them through theflux-box, and between a pairof coating-rollers contained in a bath of suitable flux, such as grease,if coating with melted tin, such grease or other flux beingkept, say, atabout 100 Fahrenheit above the meltingpoint of the coating metal. Theserollers pass the plates in succession to other rollers, all contained inthe same bath of flux. We keep the coatingrollers on the entrance sideof the coating-bath of grease or other flux well supplied with'coatingmetal.

We regulate the height of the coating metal in the roller'supply troughsby the supply produced from the pump working at a quicker or a slowerspeed.

The quality of that pumped up from the bottom of the bath will beinferior, in consequence of use, to the fresh melted metal from thereservoir, which is supplied to the exitrollers.

,Before starting the process we completely 1 than one pair of lowercoating-rollers B exit. ing metal of good quality from the tank G.

of a pump. rollers F F supplies the lower rollers F F with coatingmetal, and any metal which falls them revolving while coating metal issupplied to them.

Figure 1 represents the coating'grease pot, with troughs and rollers andmachinery, together with a reservoir, also with a revolving drum or rimand arms and guides. Fig. 1 is a vertical section.

The plate is placed in the flux-box A, and at the right moment thefinger H, acted upon by a catch and suitable levers, as shown, allowsthe plate to fall into the nip of the rollers B B and B B Below B Bthere is an iron receiver, 0 C, which collects the coating metal as itdrops from the rollers B B, and

brings it into contact with the plate as it passes downward in the spacebetween said troughs O O. The rollers B B are supplied with meltedcoating metal by the pump and gutter J, and may suitably be from six toThere may be more After the plate leaves the lower rolls B B it eightinches in diameter.

' falls onto pegs K, fixed in the drum E, and is carried round betweenthe drum E and the guides D D, until it enters the nip ofthe rollers F Fand F F through which it makes its The rollers F F are supplied withcoat- The supply to the tank G may be by means Any metal which fallsfrom the from the lower rollers F- F is taken up by the pump J, or inany other suitable manner, and supplied to the rollers B. Thus therollers F F and F F 'always receive the fresh metal,

"and after being used upon them the metal passes to the rollers B B; orthe supplies may be kept entirely-distinct, that to the rollers F and Fbeing of the better quality.

The bottom or lower part of the coating pot or vessel A is made roundedor cylindrical, in order that the space between said pot and the drum Emay be lessened, and thereby have as little grease and coating metal inthe pot a as possible. The space in the pot A maybe filled with flux orgrease, and the plates only receive the coating metal from the rollers BB' F F except that which they receive as they pass between the cylinderE and pot A, and which drips from said rollers; or a regulated quantityof coating metal may be kept in the bottom of said pot for the plates topass through. In either case the rollers f aid in transferring the metalto the plates as well as propelling them along.

Fig. 2 shows a vertical section of a somewhat different arrangement.Here the plate passes through the flux-box A into the nip of the rollersB B and B B These are fed with coating metal from the gutters G O, whichare supplied by a pump or by other convenient means. The rollers alsorevolve in troughs D D, which contain melted coating metal,and

between the'upper pair of rollers F F the plate makes its exit. Thetroughs L L of the upper pair of rollers F F are suppliedwith meltedcoating metal of a better quality from a small tank, K. At the ends ofthe rollers B B B B and F F there are nip-pieces B B which ride ingrooves in the rollers, and hinder the coating metal or flux fromrunning out at the ends of the rollers as fast as it would do otherwise.The drum and rollers are all driven by wheels gearing into each other,so that they have the same surface speed. The hollow box M displaces alarge amount of grease or flux, so that by raising or lowering it thelevel of the grease is readily-altered.

' It will, for some qualities ot' iron, be desir-' able, after thesheets are delivered by the upper or exitrollers F F, Fig. 2, or F F,Fig. 1, to submit them to a finishing process, which may form a separateoperation; but we prefer that it should be performed as the sheets riseout of the potfrom the said upper rollers. These rollers may, ifnecessary, be placed somewhat lower than the drawing shows, in order toadmit of the finishing-rollers and apparatus being placed abovethem. Insome cases we may dispense with the entrance coating-rollers, and also,if desired, with the-propelling coating-rollers, and, after passing theplate through the flux, cause it to pass between two or more coatingexit-rollers in'succession. The coating metal may be of the same ordifferent qualities. If we are coating with tin only, and if it isimportant that the plates should have the usual color, finish, andappearance of tin plate's made in the ordinary way, we finish them bybringing them out through coated rollers which revolve in contact withgrease up to and an inch or two above their nip. WVhen we use a sharperflux than grease for coating with tin or terne metal, say rosin orchloride of zinc, we omit the soaking of the plates in a preparatory potof hot grease. If we use chloride of zinc we add a little water to itoccasionally, if it becomes dry, and from time to time We strain andclean it. We make the upper pair of the coatingrollers on the entranceside of the coatingpot about six to eight inches in. diameter. Above andbetween the nip of these -ollcrs we place a flux-box about tenincheslfiigh, which we keep supplied with the rosin or chloride-of-zincflux. Themetal into which the mouth of the fluxbox dips keeps the fluxin the flux-box above the general level of the bath. We keep the nip ofthese rollers well supplied with coating metal, and the nip-pieces, asdescribed before, are useful in this respect. We also keep about two tofour inches of coating metal at the bottom of the bath, and from thissupply, which is further fed by the droppings from the rollers,

we keep the coating-rollers on the entrance side of the bath supplied.We shape the troughs so that there is a space of four or five inches ofmelted metal or flux surface behind the rollers, and by a tool shapedlike a very small spade, with an iron. handle, we are enabled to keepthe surface clean and free from scruff. Hoop-iron may be coated in asimilar way to that shown in Fig. 2. by passing it between a series ofcoating-rollers from the commencement to the completion of the process,also wire, if passed between rollers with suitable grooves. As alreadyindicated, the coating metal or flux which the plate gathers in thefirst stages of coating may be of a quality less suited to give finishand color to the plates than that contained in the troughs of the afteror finishing rollers. Thus we give the first coating of tin with tin ofa thicker or inferior character, and the after or finishing coating withmetal of better color, more liquid or more free from impurity. Ifcoating with terne metal, the mixture for the first coating may containrather less than one-third tin to twothirds lead. In the mixture forfinishing or the after-coatin g we use two-fifths tin to threefifthslead.

When using grease flux, that which we use in the flux-box is thick andstale, as it acts more efficiently in causing the plates to take thecoating metal. That in the troughs which feed the rollers for finishingis more fresh or clean, or liquid. If we use chloride of zinqin theearly stages of the process for coating with lead, tin, or terne metal,we pass all the plates through two coating-baths, and leave them tostand ten or twelve hours in tanks of water between the first and secondbaths, as

described in the specification of Edmund Morewoods British patent of 4thFebruary, 1869, No. 349, but which is not claimed here. If coating withspelter or zinc, we use muriate of ammonia or sal-ammoniac as a fluxmixed with a little of the chloride of zinc which the sal-ammoniac ormuriate of ammonia gathers from the surface of melted zinc when used asa flux upon it, and we refresh it with fresh sal-ammoniac, and clean itfrom ti meto time.

When coatingiron of heavy gage, or of such a nature as to take thecoating less readily, we sometimes form a deeper trough or channel ofcoating metal between the rollers by raising the nip-pieces (which weplace between the ends of the rollers) to a level with the top of thecoating-rollers n the entrance sideof the bath, and we keep tire-troughor channel thus formed supplied with coating metal by a pump; but tothis we make no claim here. In such case the plates in process ofcoating pass through this trough or channel of melted metal on their wayto the nip of the coatingrollers, and immediately before reaching them.

We are aware that exit-rollers by which plates are withdrawn from bathsof flux and passed from the nip of the rollers instantaneously into theair, have heretofore been supplied with coating metal by means more orless imperfect. Such rollers are described in the specification of. aBritish patent granted to Edmund Morewood 14th January, 1863, No. 123..

Our invention does not consist in the use of such exit-rollers, as it isessential to our method that a plate, after coating metal has beenapplied to its surface by rollers, should travel for a considerabledistance through flux before emerging, so that the flux may have time toact on and repair the imperfections of the coating. Whenever a plate iswithdrawn from the coating-bath while the coating is imperfect, the airacts upon it and forms a film, which it is difficult afterward todisplace.

We claima l. The coatingrollers B B and F F, in combination with the potA and drum E, substantially as and for the purposes set forth.

2. The rotary drum E in the coatingpot A, filling up the middle of saidpot, and leaving a narrowchannel or space for the passage of the plates,substantially as and for the purposes set forth.

3. The coating-rollers F and rotary drum E. in combination with the potA, substantially as and for the purposes set forth.

4-. The troughs O U, with a narrow channel between them, through which astream of coating metal is caused to flow, in combination with thecoating-rollers B, substantially as and for the purposes set forth.

5. The coating-rollers B F, receiving the melted coating metal or flux,which is retained thereon by nip-pieces B in combination with thetroughs D or L, substantially as set forth.

6. The hollow vessel M, placed Within the coating-pot, in combinationwith the drum E and coa-tingrollers, substantially as set forth.

EDMUND MOREWOOD. J. H. ROGERS.

Witnesses:

I. BEACON PHILLIPS, Bank, Llanelly. B. WILLIAMS,

Servant to Mr. B. Jones, LZa-nelly.

